Calendar clock



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CALENDAR CLOCK Filed Sept. 12, 1931 3 Sheets-Sheet l WWI ie a vzew 7 2,19136. L. HAMMOND 2,2337

CALENDAR CLOCK Filed Sept. 12, 1.951 5 Sheets-Sheet 2 J2 g .61 J10 J14L. HAMMOND 2,042,337

CALENDAR CLOCK Filed. Sept. 12, 1931 3 Sheets-Sheet 3 /%@W CR PatentedMay 26, 1936 UNITED STATES PATENT OFFICE CALENDAR CDOCK Laurens Hammond,Evanston, Ill., assignor to The Hammond Clock Company, Chicago, 111., acorporation of Delaware Application September 12, 1931, Serial No.582,459 I 3 Claims.

My invention relates generally to calendar clocks, and more particularlyto improvements in the operating mechanism for the day and dateindicating mechanisms of such clocks.

It is an object of my invention to provide a simplified mechanism foroperating day of the week and date indicating means in conjunction withan electric clock.

A further object is to provide a calendar clock which has a small numberof operating parts, in which the operation is certain, in which most ofthe parts are stampings, and which may be economically manufactured.

A further object is to provide an improved calendar clock in which theday of the week and date indicating means may readily be reset.

A further object is to provide an improved calendar clock having twoindicators, one for the units and one for the tens indication of thedate of the month, and to provide common means for actuating said unitsand tens indicators without the necessity of employing a transfermechanism.

Other objects will appear from the following description, referencebeing. had to the accompanying drawings, in which Figure l is aperspective view of the complete clock;

Figure 2 is a vertical sectional view of the clock casing with the handsand dial removed; Figure 3 is a sectional view taken on the line 3-3 ofFig. 2

Figure 4 is a sectional view taken on the line 44 of Fig. 2; Figure 5 isa bottom plan view of the clock;

Figure 6 is a sectional detail showing the actuating means for the dateindicating wheels;

Figure '7 is a view similar to Fig. 2 with the front dial supportingplate broken away to show the parts located beneath it;

Figure 8 is a side elevation showing the detent means for holding theindicating wheels; and

Figure 9 is a fragmentary sectional view taken on the line 9---9 of Fig.2.

The clock comprises a molded case In, which may be moldedof a suitablephenol condensation product, having four soft rubber feet I! which fitinto recesses in the base of the casing. The mechanism of the clock issupported by a pair of spaced frame plates l4, Hi, to which are attachedaback-cover plate l8 and a front plate 26. ter is covered by a dial 22,which is secured to' the front plate 20 by having corner lugs 24 (Fig.8) thereof bent around the plate 20,

corners of the plate 20. A sheet 21 of glass is held between theperipheral edge flange of the dial 22 and a bezel flange 28 formedaround the The entire clock works are held in the case by screws 30. Theplate 20 has a plurality of depressed portions 32 struck therefrom,these portions being fastened to the plate l6 by means of nuts and bolts34.

The clock mechanism may be of any suitable construction, but ispreferably synchronous motor A satisfactory mechanism of this type isdisclosed in my copending application Serial No. 390,551, filedSeptember 5, 1929, now Patent No. 1,924,853, dated August 29, 1933.

, As best shown in Fig. 7, the hour hands of the clock are driven from apinion 36 which meshes with the gear 38 secured to the hour-handsleeve40. The gear 38 has a pinion 42 rigidly secured thereto, the lattermeshing with a gear 44. As illustrated in Fig. 2, the shaft 45 uponwhich the gear 44 is fixed has secured thereto a disc 41, which ispositioned within a depression formed in the front plate 20. The halvesof the disc 41 are colored in contrasting colors and a small portion ofthis disc is visible through a small aperture 49 formed in the dialplate 22.

A pin 46 secured to the gear 44 projects outwardly therefrom so as tolie within an irregularly shaped opening 48 -formed within the enlargedportion 56 of a lever 52. The lever 52 is pivoted at 54 and has its freeextremity pivotally connected to a vertically slidable bar 56 by a stud53. This bar is guided by a pair ofshouldered rivets 58, which aresecured to the front plate 20. A pair of pawls 60 and 62, which arepreferably integral and punched from a sheet of spring steel, areriveted to the lower end of the bar 56.

A pair of brackets 64, 66, struck from the plate 20, form bearings for ashaft 68. The shaft has an annular groove adjacent each end thereof toreceive a retaining spring clip 10.

The shaft 68 serves as the pivotal support for three wheels or drums 12,14 and 16, which form indicators for the days of the week, and the tensand the units of the days of the month, respectively. The drum 12comprises a drawn shell 18 (Fig. 4), one end of which is closed by adished head 80, having a notched outwardly extending rim 82 forengagement with a spring detent 84, which is riveted to the plate 20 atA ratchet wheel 86 is riveted to the other end of the shell 18, saidratchet having seven equally spaced teeth. The tens drum 14 iscupshaped, having its end wall secured to a sleeve 88, to which issecured a ratchet wheel 90.

front of the case In.

The

drum (4 has a flanged rim 89 with ten notches therein for engagementwith a detent 9| (Fig. 2). The units drum I6 is likewise cup-shaped,having its end wall 92 secured to a sleeve 94, which is rotatablymounted on a shaft 68. The rim 93 of the drum I6 has ten notches thereinfor cooperation with detent 95. The sleeve 94 carries a ratchet wheel 96which lies closely adjacent the ratchet wheel 90; the two ratchet wheelsbeing held apart, and hence the drums I4 and I6 held close together by aspider spring 98.

The ratchet wheels 90 and 96 each have ten teeth but the root diameterof the ratchet wheel 96 is greater than the outside diameter of theratchet wheel 90, there being, however, a single notch in the ratchetwheel 96, which is approximately twice as deep as the remaining notcheson this wheel, for a purpose which will be described hereinafter.

A certain amount of frictional drag is imposed upon the drum I6 by acoil spring I00 which is wound about a guide sleeve I02 which isshouldered to form a seat for one end of the spring, the other end ofthe spring engaging the end wall 92 of the drum I6.

' A stop member I04 has one end passing through a suitable opening inthe front plate 20 and has an apertured lug I06 riveted thereto. Thislug fits between the two ratchet wheels 86 and 96, the member having apair of sidewardly extending projections I08 which limit inward movement(to the left,'Fig. 3) of the ends of the spring pawls 62 when the latterare in their uppermost position.

The base of the case I0 is provided with apertures H0, H2 and H4, whichare sufficiently large to permit the manual rotation of the drums I2, I4and 16 to set the lattter. suitably marked with the days of the week,the drum 14 with duplicate sets of numerals I, 2, 3" and the word Set,while the drum I6 is marked with the numerals 0 to 9", inclusive.

The operation of the clock is as follows: The pinion 42 rotates with thegear 38 at a speed of one revolution in twelve hours. The gear 44 hastwice as many teeth as the pinion 42 and hence will make one revolutionin twenty-four hours. The gear 44 rotates in the direction of the arrowshown in Fig. 7 and through engagement of its pin 46 with the edges ofthe opening 48 swings the lever 52 upwardly about its pivot 54, therebyraising the-slide-bar 56. This operation takes place relatively slowly.After the gear 44 has rotated approximately 180 counterclockwise fromthe position in which it is shown in Fig. 7, it will cause a rapiddownward movement of the bar 56, this movement taking place duringangular displacement of less than 30 on the gear 44 due to the shape ofthe opening 48. Downward movement of the bar 56 to its lowermostposition is assured by the engagement of the pin 46 with the lower edgeof the opening 48.

During this downward movement of the slidebar 56, the pawls 60 and 62will engage the teeth of the ratchet wheels 86 and 96, thereby rotatingthe latter and the drums to which they are connected. The ratchet wheel86 will, due to the spacing teeth, be rotated through one-seventh of arevolution, whereas the ratchet wheel 96 will be rotated throughone-tenth of a revolution. Although both pawls 60 and 62 have the samelength stroke, the stroke is just sufficient for the pawl 62 to travel adistance equal to or slightly greater than that between the teeth Thedrum 121s of the ratchet wheel 86 but not suflicient to travel twice thelength of the spaces between the teeth of the ratchet wheel 96. Thus atthe beginning of a downward stroke, the pawl 62 will first engage atooth of the ratchet wheel 86 and move 5 the latter a short distanceand, thereafter, the pawl 60 will engage a tooth of the ratchet wheel96. After the pawl 60 thus operatively engages the ratchet wheel 96, thepawl will continue its downward movement and rotate the ratchet 10 wheel96 through an angle of 36, at the same time completing the rotation ofratchet wheel 86 through one-seventh of a revolution. Rotation of thedrums is limited and overthrow prevented through engagement of detents84, 9| and 15 95 in the notches of the flanges 82, 89 and 93,respectively.

When the units drum is in a position to indicate the digit 9, the deepnotch in the ratchet wheel 96 will lie beneath the pawl 60 and the 20latter will thereby move inwardly toward the shaft 68 sufiicient toengage one of the teeth of the ratchet wheel 90. The ratchet wheels 90,96, and hence their drums I4, 16, will be moved together one-tenth of arevolution so as to register 25 10". This mechanism thus performs thefunctions of a transfer or marry-over mechanism. The indicia upon thevarious drums are visible through openings H8 and I20 formed in the dialplate 22, as best shown in Fig. 1.

' The calendar date indicating mechanism operates automatically for onlyone month, it being necessary manually to reset the date indicatingdrums at the end of each month. If this resetting is neglected for tendays the word Set 35 will appear on the tens drum through the sightopening I20.

In view of the fact that it is necessary that the calendar indicationschange during the night, the clock must, be set not only to thecorrect'40 hour and minute, but also with reference to whether the timeis A. M. or P. M. This can be ascertained by noting the color 01' theportion of the disc appearing through the aperture 49.

It will be noted that the operating mechanism 5 for the day and dateindicators is positive, that setting also greatly simplifies theconstruction. 55

While I have illustrated and described a preferred embodiment of myinvention, many modifications may be made without departing from thespirit of the invention, and I do not wisli to be limited to the precisedetails set forth but 60 desire to avail myself of all changes withinthe scope of the appended claims.

1. In a clock,the combination of a clock mecha nism having a pinionrotatable once in twelve hours, a gear driven by said pinion, apivotally 65 mounted lever, interengaging means on said lever and gearfor causing oscillation of said lever upon rotation of said gear, aslidably mounted bar pivoted to the free end of said lever, a pluralityof indicating members, and means associated with 70 said bar and saidmembers to cause diverse degrees of angular movement of said membersupon reciprocation of said bar by said lever.

2. A day and date indicating means for clocks comprising a plurality ofindicating drums having the days of the week, the tens of the date and"the units of the date respectively marked thereon, each of said drumshaving a ratchet wheel fixed thereto, all of said ratche, wheels beinglocated side by side adjacent one another, the ratchet wheel fixed tosaid day indicating drum having seven equally spaced teeth, the ratchetwheel fixed to said date units indicating drum having ten equally spacedteeth, and a deep notch formed between two of the teeth thereof, theratchet wheel fixed to said tens date indicating drum being of smallerdiameter than the ratchet wheel fixed to the units date indicating drumand having a plurality of spaced teeth; a shaft common to all of saiddrums and forming a support therefor, pawl m'eans engageable with saidratchet wheels to rotate said drums, said pawl means including a commonpawl engageable with the ratchet wheels fixed to said units-and tensdate indicating drums but held from engagement with the former exceptwhen the deep notch of the ratchet wheel of said units date indicatingdrum is in position to be engaged thereby, whereby said tens dateindicating drum will be operated one space each time said units dateindicating drum is rotated through a complete revolution.

3. In a clock, the combination of a clock mechanisnr, a memberreciprocated once in twentyfour hours by said mechanism, three rotatabledrum-shaped indicators each having a ratchet wheel associated therewith,a shaft common to said indicators for supporting them for rotation, saidratchet wheels having different numbers of spaced teeth thereon andbeing located immediately adjacent one another, resilient pawls securedto said reciprocating member and engageable with said ratchet wheels torotate the latter diverse angular distances upon reciprocatory movementthereof, manually engageable rims on said indicators, and detent meanscooperable with said rims for holding said indicators in position. 20

LAURENS HAMMOND.

